CN106351894A - Open model pump control load cavity independent control asymmetrical cylinder power unit - Google Patents
Open model pump control load cavity independent control asymmetrical cylinder power unit Download PDFInfo
- Publication number
- CN106351894A CN106351894A CN201610916687.2A CN201610916687A CN106351894A CN 106351894 A CN106351894 A CN 106351894A CN 201610916687 A CN201610916687 A CN 201610916687A CN 106351894 A CN106351894 A CN 106351894A
- Authority
- CN
- China
- Prior art keywords
- variable displacement
- displacement pump
- way variable
- overflow valve
- bidirectional variable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
- F15B11/028—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/04—Special measures taken in connection with the properties of the fluid
- F15B21/042—Controlling the temperature of the fluid
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20507—Type of prime mover
- F15B2211/20515—Electric motor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20546—Type of pump variable capacity
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20576—Systems with pumps with multiple pumps
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses an open model pump control load cavity independent control asymmetrical cylinder power unit which comprises an overflow valve A, a motor, a bidirectional variable pump A, a bidirectional variable pump B, an oil tank, an overflow valve B and a hydraulic cylinder, wherein the power levels of the bidirectional variable pump A and the bidirectional variable pump B are different; the motor, the bidirectional variable pump A and the bidirectional variable pump B are in coaxial and serial connection; a low-pressure oil port of the bidirectional variable pump A is communicated with the oil tank, and a high-pressure oil port of the bidirectional variable pump A is connected with the overflow valve A and a rodless cavity of the hydraulic cylinder; a low-pressure oil port of the bidirectional variable pump B is communicated with the oil tank, and a high-pressure oil port of the bidirectional variable pump B is connected with the overflow valve B and a rod cavity of the hydraulic cylinder. As two bidirectional variable pumps with different power levels are utilized to be respectively matched with two cavities of the actuator, the match between a power system and a load is achieved, and the power loss of a hydraulic system is reduced; furthermore, the controllability freedom of the system is improved, and the dynamic and static characteristics of the system are improved.
Description
Technical field
The present invention relates to field of hydraulic control, especially a kind of asymmetrical cylinder hydraulic power unit.
Background technology
In recent years, with the development of pump control technology, people are to the control performance of pump control hydraulic control system and energy conservation characteristic
Requirement also more and more higher.Traditional pump control asymmetrical cylinder hydraulic control system mostly is closed system, due to hydraulic cylinder two Cavity surface
Long-pending difference, causes hydraulic cylinder two ends flow asymmetric；And closed system fluid recycled in the working cycle, caused system
Caloric value is big.
Load port independent technique is used in valve control system, and system controls one to hold using two independent restrictions respectively
The flow of the oil inlet and outlet of row device or pressure, solve the problems, such as that in control system, load flow coupling is not enough, increased system
Control freedom degree, improve the static and dynamic performance of system.However, the research for load port independent control technology is mainly concentrated
In valve control system, limit its advantage in terms of energy-conservation to a certain extent.Therefore, by load chamber independent control technology
Combine the static and dynamic performance being conducive to improvement system and the purpose realizing energy-conservation with open model pump control.
Content of the invention
Present invention aim at providing, a kind of structure is simple, the loss of asymmetrical cylinder two chamber flow equilibrium, system power is little
Open model pump control load chamber independent control asymmetrical cylinder power unit.
For achieving the above object, employ technical scheme below: power unit of the present invention includes motor, bidirectional variable
Pump a, two-way variable displacement pump b, fuel tank and hydraulic cylinder；The power level of two-way variable displacement pump a, b is different, controls executor two chamber respectively
Flow or pressure；Motor, two-way variable displacement pump a, two-way variable displacement pump b coaxially connect；The low pressure hydraulic fluid port of two-way variable displacement pump a and oil tank joint
Logical, the high pressure hydraulic fluid port of two-way variable displacement pump a is connected with the rodless cavity of hydraulic cylinder；The low pressure hydraulic fluid port of two-way variable displacement pump b is connected with fuel tank,
The high pressure hydraulic fluid port of two-way variable displacement pump b is connected with the rod chamber of hydraulic cylinder.
Further, described power unit also includes overflow valve a and overflow valve b, and the high pressure hydraulic fluid port of two-way variable displacement pump a is respectively
It is connected with the rodless cavity of overflow valve a one end, hydraulic cylinder, the overflow valve a other end is connected with fuel tank；The hydraulic oil of two-way variable displacement pump b
Mouth is connected with the rod chamber of overflow valve b one end, hydraulic cylinder respectively, and the overflow valve b other end is connected with fuel tank.
Work process approximately as:
Two-way variable displacement pump enters hydraulic cylinder from fuel tank oil suction, and hydraulic cylinder oil return returns fuel tank, and working oil cools down in fuel tank
Enter back into cycle of operation.Using load chamber independent control technology, increase the controllable degrees of freedom of system, make executor (asymmetric
Cylinder) can be independent according to demand in motor process the flow in adjusting actuator two chamber or pressure.Using position pressure bonding
Control strategy, by improving the back pressure of exhaust chamber, makes the rigidity of system increase, and reduces carrying to hydraulic cylinder piston rod displacement
Impact, the position control accuracy of lift system.The increase of simultaneity factor rigidity, makes the natural frequency of system increase, and accelerates system
Response.
Compared with prior art, the present invention has the advantage that
1st, system radiating is good, save recharging oil device, and system structure is simple, solves conventional pump control asymmetrical cylinder two chamber stream
Measure unbalanced problem.
2nd, two different two-way variable displacement pumps of power level match with executor's (asymmetrical cylinder) two chamber respectively it is achieved that
Dynamical system is mated with load, decreases the power loss of hydraulic system.
3rd, the structure connected with motor coaxle using two two-way variable displacement pumps, impedance is stretched out during pattern or impedance retraction pattern
When exhaust chamber side two-way variable displacement pump be in motor operating conditions, reclaim hydraulic energy, hydraulic energy be changed to the mechanical energy of motor shaft simultaneously, from
And reduce the output torque of motor, make system have higher energy transfer efficiency.
Brief description
Fig. 1 is the structure principle chart of the present invention.
Fig. 2 is the power source main shaft force diagram of the present invention.
Fig. 3 is that the present invention adopts position pressure bonding control strategy block diagram.
Drawing reference numeral: 1- overflow valve a, 2- motor, 3- two-way variable displacement pump a, 4- two-way variable displacement pump b, 5- fuel tank, 6- overflow valve
B, 7- hydraulic cylinder.
Specific embodiment
The present invention will be further described below in conjunction with the accompanying drawings:
As shown in figure 1, power unit of the present invention includes overflow valve a1, motor 2, two-way variable displacement pump a3, bidirectional variable
Pump b4, fuel tank 5, overflow valve b6 and hydraulic cylinder 7；The power level of two-way variable displacement pump a, b is different, the rod chamber with hydraulic cylinder respectively
Match with rodless cavity, wherein,Motor, two-way variable displacement pump a, two-way variable displacement pump b coaxially connect；Two-way variable displacement pump a
Low pressure hydraulic fluid port and fuel tank connect, the high pressure hydraulic fluid port of two-way variable displacement pump a is connected with the rodless cavity of overflow valve a, hydraulic cylinder respectively, excessive
The other end of stream valve a is connected with fuel tank；The low pressure hydraulic fluid port of two-way variable displacement pump b is connected with fuel tank, the high pressure hydraulic fluid port of two-way variable displacement pump b
It is connected with the rod chamber of overflow valve b, hydraulic cylinder respectively, the other end of overflow valve b is connected with fuel tank.
Two overflow valves only play safeguard protection effect.And two-way variable displacement pump enters hydraulic pressure, hydraulic cylinder oil return from fuel tank oil suction
Return fuel tank, working oil cools down in fuel tank and enters back into next cycle of operation, and therefore open model pump control system radiating is good.With
When, because hydraulic cylinder two ends connect two two-way variable displacement pumps a, b respectively, and the discharge capacity of two two-way variable displacement pumps can individually control,
Therefore increased the controllable degrees of freedom of system；Hydraulic cylinder can be independent according to demand in motor process regulation two chamber flow
Or pressure, solve the unbalanced problem of pump control asymmetrical cylinder two cavity volume flow.
Fig. 2 is the power source main shaft force diagram of the present invention., stretched out as a example pattern by impedance, due to motor and bidirectional variable
Pump a and two-way variable displacement pump b coaxially connects, and in motor process, two-way variable displacement pump a changes discharge capacity according to load change provides system
Necessary flow, two-way variable displacement pump b reclaims hydraulic energy with motor operating conditions, then is converted into the mechanical energy of mechanical axis in the form of torque,
Thus reducing the torque of motor output.As shown in Fig. 2 motor output torque t1=t2-t3.
Fig. 3 is that the present invention adopts position pressure bonding control strategy block diagram.In conjunction with shown in Fig. 1 and Fig. 3, hydraulic cylinder two ends are divided
Not Lian Jie two-way variable displacement pump a, b, can individually control the discharge capacity of two-way variable displacement pump a, b, therefore increased the controllable degrees of freedom of system.
Wherein admission chamber adopts position-force control, and back pressure cavity adopts pressure closed loop to control.According to system condition, pid controller 1 basis
The feedback signal of displacement transducer, is compared with given displacement, obtains offset deviation signal, controls liquid feeding side two-way variable displacement pump
The discharge capacity of a, and then control the displacement of hydraulic cylinder.Pid controller 2 according to the feedback signal of pressure transducer, with given back pressure ratio
Relatively, obtain pressure divergence signal, control the discharge capacity of exhaust chamber two-way variable displacement pump b, carry out the Pressure in Back-pressure Cavity closed loop control of hydraulic cylinder
System.The raising of system back pressure cavity pressure, increases the rigidity of system, is beneficial to reduce the impact to hydraulic cylinder displacement for the carrying,
Thus improving the position control accuracy of system.Additionally, the increase of system stiffness, also improve the natural frequency of system, accelerate
The response of system.
Embodiment described above is only that the preferred embodiment of the present invention is described, the not model to the present invention
Enclose and be defined, on the premise of without departing from design spirit of the present invention, the technical side to the present invention for the those of ordinary skill in the art
Various modifications and improvement that case is made, all should fall in the protection domain of claims of the present invention determination.
Claims (2)
1. a kind of open model pump control load chamber independent control asymmetrical cylinder power unit it is characterised in that: described power unit bag
Include motor, two-way variable displacement pump a, two-way variable displacement pump b, fuel tank and hydraulic cylinder；The power level of two-way variable displacement pump a, b is different, respectively
Control flow or the pressure in executor two chamber；Motor, two-way variable displacement pump a, two-way variable displacement pump b coaxially connect；Two-way variable displacement pump a's
Low pressure hydraulic fluid port is connected with fuel tank, and the high pressure hydraulic fluid port of two-way variable displacement pump a is connected with the rodless cavity of hydraulic cylinder；Two-way variable displacement pump b's is low
Force feed mouth and fuel tank are connected, and the high pressure hydraulic fluid port of two-way variable displacement pump b is connected with the rod chamber of hydraulic cylinder.
2. a kind of open model pump control load chamber independent control asymmetrical cylinder power unit according to claim 1, its feature
Be: described power unit also includes overflow valve a and overflow valve b, the high pressure hydraulic fluid port of two-way variable displacement pump a respectively with overflow valve a mono-
End, the rodless cavity of hydraulic cylinder are connected, and the overflow valve a other end is connected with fuel tank；The high pressure hydraulic fluid port of two-way variable displacement pump b respectively with overflow
Valve b one end, the rod chamber of hydraulic cylinder are connected, and the overflow valve b other end is connected with fuel tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610916687.2A CN106351894A (en) | 2016-10-21 | 2016-10-21 | Open model pump control load cavity independent control asymmetrical cylinder power unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610916687.2A CN106351894A (en) | 2016-10-21 | 2016-10-21 | Open model pump control load cavity independent control asymmetrical cylinder power unit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106351894A true CN106351894A (en) | 2017-01-25 |
Family
ID=57863438
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610916687.2A Pending CN106351894A (en) | 2016-10-21 | 2016-10-21 | Open model pump control load cavity independent control asymmetrical cylinder power unit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106351894A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106640780A (en) * | 2017-02-24 | 2017-05-10 | 上海振华重工(集团)股份有限公司 | Positive displacement heave compensation hydraulic system and heavy compensation lifting system |
| CN108194437A (en) * | 2018-02-28 | 2018-06-22 | 福建工程学院 | A kind of potential energy recycling and the pump hydraulic energy conserving system of electric machine speed regulation |
| CN108425893A (en) * | 2018-04-17 | 2018-08-21 | 福建工程学院 | A kind of distributed direct drive excavator hydraulic system of servo motor driving bivariate pump |
| CN109139584A (en) * | 2018-11-05 | 2019-01-04 | 深圳航天科技创新研究院 | Pump valve multiplex control system and method |
| CN112629789A (en) * | 2020-12-17 | 2021-04-09 | 徐州徐工挖掘机械有限公司 | Fuel tank vibration durability test device and method |
| CN113124005A (en) * | 2021-03-17 | 2021-07-16 | 太原理工大学 | Double-pump separated-cavity regulation control load simulation system |
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| CN206129750U (en) * | 2016-10-21 | 2017-04-26 | 燕山大学 | Asymmetric jar power pack of chamber independent control is held in open pump control load |
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| JP3112300B2 (en) * | 1991-03-29 | 2000-11-27 | 株式会社アマダ | Plate processing machine |
| JPH07127606A (en) * | 1993-11-05 | 1995-05-16 | Tokimec Inc | Electro-hydraulic pressure transmission device |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106640780A (en) * | 2017-02-24 | 2017-05-10 | 上海振华重工(集团)股份有限公司 | Positive displacement heave compensation hydraulic system and heavy compensation lifting system |
| CN106640780B (en) * | 2017-02-24 | 2018-12-25 | 上海振华重工(集团)股份有限公司 | A kind of positive displacement heave compensation hydraulic system and heave compensation Lift-on/Lift-off System |
| CN108194437A (en) * | 2018-02-28 | 2018-06-22 | 福建工程学院 | A kind of potential energy recycling and the pump hydraulic energy conserving system of electric machine speed regulation |
| CN108194437B (en) * | 2018-02-28 | 2023-10-24 | 福建工程学院 | Double-pump hydraulic energy-saving system for potential energy recovery and motor speed regulation |
| CN108425893A (en) * | 2018-04-17 | 2018-08-21 | 福建工程学院 | A kind of distributed direct drive excavator hydraulic system of servo motor driving bivariate pump |
| CN108425893B (en) * | 2018-04-17 | 2023-11-17 | 福建工程学院 | Hydraulic system of distributed direct-driven excavator with servo motor driven double variable pumps |
| CN109139584A (en) * | 2018-11-05 | 2019-01-04 | 深圳航天科技创新研究院 | Pump valve multiplex control system and method |
| CN112629789A (en) * | 2020-12-17 | 2021-04-09 | 徐州徐工挖掘机械有限公司 | Fuel tank vibration durability test device and method |
| CN112629789B (en) * | 2020-12-17 | 2023-09-12 | 徐州徐工挖掘机械有限公司 | Fuel tank vibration durability test device and method |
| CN113124005A (en) * | 2021-03-17 | 2021-07-16 | 太原理工大学 | Double-pump separated-cavity regulation control load simulation system |
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Application publication date: 20170125 |
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